Abdullah bin Buraydah narrates from Imran bin Husayn (may Allah be pleased with him): I had haemorrhoids, so I asked the Prophet (peace and blessings be upon him). He (peace and blessings be upon him) said: "Pray standing; if you are unable, then pray sitting; and if you are unable even to do that, then pray lying on your side."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 5488
Maymun bin Mihran narrates from Ibn Umar (may Allah be pleased with them both) that the Prophet (peace and blessings be upon him) was asked about praying in a boat: "How should we pray in a boat?" He (peace and blessings be upon him) said: "Pray standing, unless you fear drowning."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 5489
Maymun bin Mihran narrates from Ibn Umar (may Allah be pleased with them both) that the Messenger of Allah (peace and blessings be upon him), when his Companions were setting out for Abyssinia, ordered them: "Pray standing in the boat as long as there is no fear of drowning."
Thus he narrated it; there is disagreement about it over Abdullah bin Dawud, and it is said that he did not hear it from Ja'far. The hadith of Abu Nu'aym al-Fadl bin Dukayn is hasan (good).
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 5490
Maymun bin Mihran narrates from Sayyiduna Ibn Abbas (may Allah be pleased with them both) that when Sayyiduna Ja'far bin Abi Talib (may Allah be pleased with him) and his companions (may Allah be pleased with them) went to Abyssinia, they used to pray standing in the boat.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 5491
Humayd al-Tawil (may Allah have mercy on him) said: Anas bin Malik (may Allah be pleased with him) was asked about praying in a boat. Abdullah bin Abi Utbah (may Allah have mercy on him), the freed slave of Anas (may Allah be pleased with him), who was with us in the gathering, said: I travelled with Abu al-Darda' (may Allah be pleased with him), Abu Sa'id al-Khudri (may Allah be pleased with him) and Jabir bin Abdullah (may Allah be pleased with them both); he would lead us in prayer standing in the boat, and we would pray standing behind him, and if we had wished, we could have gone out (onto land).
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 5492
Al-Nadr bin Anas narrates from Sayyiduna Anas (may Allah be pleased with him) that when he boarded a boat and the time of prayer came, if the boat was held at anchor he would pray standing, and if the boat was moving he would pray sitting, in congregation.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 5493